Raman activated cell sorting

[Display omitted] •Raman activated cell sorting (RACS) provides a label-free cell sorting approach, which can link single cells to their biological activities.•There are three challenges for developing RACS: weak Raman signal, sorting criteria and specific sorting technology.•Advances on Raman spectroscopy such as stimulated Raman scattering (SRS) and pre-screening will help increase RACS sorting speed. Entire single cell Raman spectra (SCRS) and specific Raman biomarkers can be used as sorting criteria for RACS. Recent advances on microfluidic and surface-ejection based cell sorting technologies enable accurate single cell sorting from complex samples. Single cell Raman spectra (SCRS) are intrinsic biochemical profiles and ‘chemical images’ of single cells which can be used to characterise phenotypic changes, physiological states and functions of cells. On the base of SCRS, Raman activated cell sorting (RACS) provides a label-free cell sorting approach, which can link single cells to their chemical or phenotypic profiles. Overcoming naturally weak Raman signals, establishing Raman biomarker as sorting criteria to RACS and improving specific sorting technology are three challenges of developing RACS. Advances on Raman spectroscopy such as stimulated Raman scattering (SRS) and pre-screening helped to increase RACS sorting speed. Entire SCRS can be characterised using pattern recognition methods, and specific Raman bands can be extracted as biomarkers for RACS. Recent advances on cell sorting technologies based on microfluidic device and surface-ejection enable accurate and reliable single cell sorting from complex samples. A high throughput RACS will be achievable in near future by integrating fast Raman detection system such as SRS with microfluidic RACS and Raman activated cell ejection (RACE).